Storyline: The NFL couldn't have set up a juicier matchup for Peyton Manning's return. Although the Steelers' defense needed to replace some key parts, and safety Ryan Clark can't play in Denver for health reasons, this is still a formidable challenge for the four-time MVP as he makes his Broncos debut in prime time. Pittsburgh was eliminated from the playoffs on the first play of overtime in the Mile High City in January on Tim Tebow's 80-yard completion to Demaryius Thomas.